"ps -e" without procfs(5)

[Mikolaj Golub]

On Wed, 9 Nov 2011 14:53:29 +0200 Kostik Belousov wrote:

 >> > http://people.freebsd.org/~trociny/env.sys.4.patch
 >> > 
 >> > Investigating cases when EFAULT was returned and if the fallback was
 >> > successful I noticed that most of the cases were when p->p_comm changed during
 >> > the read, so the process was in exec in that time. In order to avoid this
 >> > error I added a check for P_INEXEC flag.
 >> And now you return success and nothing gets copied out for the process
 >> in P_INEXEC state. Either you should return an error like EAGAIN, or
 >> consider the P_INEXEC state as transitional and wait till process
 >> leaves it. Or, ignore the state as it was before, and return whatever
 >> error proc_rwmem generated (my preference).

 KB> Forgot to say that the check does not change much because you drop
 KB> process lock immediately after the check, so the process may enter
 KB> the INEXEC state right after the check. I believe you already tried
 KB> to do this with P_WEXIT.

Ok, eventually I decided not to check for P_INEXEC (as the simplest :-).

The updated patch:

http://people.freebsd.org/~trociny/env.sys.5.patch

-- 
Mikolaj Golub